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"Unsupported Version of Firefox"

  • 2 replies
  • 1 has this problem
  • 1 view
  • Last reply by cor-el

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I have updated FF every time a new version comes out. I'm on FF 76.0.1 for MacOS.

Several websites "warn" me that I'm on an unsupported version of FF, and to update to the newest version. Some sites won't even let me continue, but only give me the option to close the tab, or go to the Mozilla site to download the newest version.

I've seen the response to a Windows user with the similar problem, and have gone through all the steps of checking general.useragent.compatMode.firefox and it's set to "false" and none of the settings needed to be changed. I also checked the privacy.resistFingerprinting and it is set to "false".

I'm tired of websites thinking I'm using FF 56, when I'm using FF 76.0.1!! MacBook Pro mid-2014, OSX 10.14.6 Mojave, 16 GB RAM DDR3, 2.8GHz Intel Core i7, Firefox 76.0.1 (64-bit).

Installed plugins include Shockwave Flash as noted, but there are a few websites I use for work that stubbornly still require Flash :(


Help????

I have updated FF every time a new version comes out. I'm on FF 76.0.1 for MacOS. Several websites "warn" me that I'm on an unsupported version of FF, and to update to the newest version. Some sites won't even let me continue, but only give me the option to close the tab, or go to the Mozilla site to download the newest version. I've seen the response to a Windows user with the similar problem, and have gone through all the steps of checking '''general.useragent.compatMode.firefox''' and it's set to "false" and none of the settings needed to be changed. I also checked the '''privacy.resistFingerprinting''' and it is set to "false". I'm tired of websites thinking I'm using FF 56, when I'm using FF 76.0.1!! MacBook Pro mid-2014, OSX 10.14.6 Mojave, 16 GB RAM DDR3, 2.8GHz Intel Core i7, Firefox 76.0.1 (64-bit). Installed plugins include Shockwave Flash as noted, but there are a few websites I use for work that stubbornly still require Flash :( Help????

All Replies (2)

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I've added 2 screen shots of "your browser is out of date" that popped on different websites this morning.

Rather frustrating, since they seem to think I'm on version 56, when I'm really on version 76.0.1, I keep very current. Some sites refuse to allow me to continue, so I have to change to Chrome or Safari!

I've already done all the troubleshooting suggested for the Windows fellow who had a similar problem.

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You can check for problems with preferences. You can delete possible user.js and numbered prefs#-##.js files and rename/remove the prefs.js file to reset all prefs to the default value including prefs set via user.js and prefs that are no longer supported in current Firefox releases.

You can use the button on the "Help -> Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page.

You can try these steps in case of issues with web pages:

You can reload web page(s) and bypass the cache to refresh possibly outdated or corrupted files.

  • hold down the Shift key and left-click the Reload button
  • press "Ctrl + F5" or press "Ctrl + Shift + R" (Windows,Linux)
  • press "Command + Shift + R" (Mac)

Clear the Cache and remove the Cookies for websites that cause problems via the "3-bar" Firefox menu button (Options/Preferences).

"Remove the Cookies" for websites that cause problems:

  • Options/Preferences -> Privacy & Security
    Cookies and Site Data: "Manage Data"

"Clear the Cache":

  • Options/Preferences -> Privacy & Security
    Cookies and Site Data -> Clear Data -> Cached Web Content: Clear

Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration is causing the problem.

  • switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Themes
  • do NOT click the "Refresh Firefox" button on the Safe Mode start window
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You can remove all data stored in Firefox for a specific domain via "Forget About This Site" in the right-click context menu of an history entry ("History -> Show All History" or "View -> Sidebar -> History").

Using "Forget About This Site" will remove all data stored in Firefox for this domain like history and cookies and passwords and exceptions and cache, so be cautious. If you have a password or other data for that domain that you do not want to lose then make sure to backup this data or make a note.

You can't recover from this 'forget' unless you have a backup of involved files.

If you revisit a 'forgotten' website then data for that website will be saved once again.